Dual-fuel reactivity-controlled compression ignition (RCCI) combustion using port injection of a less reactive fuel and early-cycle direct injection (DI) of a more reactive fuel has been shown to yield both high thermal efficiency and low NOX and soot emissions over a wide engine operating range. Conventional and alternative fuels such as gasoline, natural gas, and E85 as the lower reactivity fuel in RCCI have been studied by many researchers; however, published experimental investigations of hydrous ethanol use in RCCI are scarce. Making greater use of hydrous ethanol in internal combustion engines has the potential to dramatically improve the economics and life cycle carbon dioxide emissions of using bioethanol. In this work, an experimental investigation was conducted using 150 proof hydrous ethanol as the low reactivity fuel and commercially available diesel as the high reactivity fuel in an RCCI combustion mode at various load conditions. A modified single-cylinder diesel engine was used for the experiments. Based on previous studies on RCCI combustion by other researchers, early-cycle split-injection strategy of diesel fuel was used to create an in-cylinder fuel reactivity distribution to maintain high thermal efficiency and low NOX and soot emissions. At each load condition, timing and mass fraction of the first diesel injection was held constant, while timing of the second diesel injection was swept over a range where stable combustion could be maintained. Since hydrous ethanol is highly resistant to auto-ignition and has large heat of vaporization, intake air heating was needed to obtain stable operations of the engine. The study shows that 150 proof hydrous ethanol can be used as the low reactivity fuel in RCCI through 8.6 bar indicated mean effective pressure (IMEP) and with ethanol energy fraction up to 75% while achieving simultaneously low levels of NOX and soot emissions. With increasing engine load, less intake heating is needed and exhaust gas recirculation (EGR) is required to maintain low NOX emissions.

References

References
1.
Dec
,
J. E.
,
2009
, “
Advanced Compression-Ignition Engines—Understanding the In-Cylinder Processes
,”
Proc. Combust. Inst.
,
32
(
2
), pp.
2727
2742
.10.1016/j.proci.2008.08.008
2.
Alriksson
,
M.
, and
Denbratt
,
I.
,
2006
, “
Low Temperature Combustion in a Heavy Duty Diesel Engine Using High Levels of EGR
,”
SAE Technical Paper No. 2006-01-0075
.10.4271/2006-01-0075
3.
Inagaki
,
K.
,
Fuyuto
,
T.
,
Nishikawa
,
K.
, and
Nakakita
,
K.
,
2006
, “
Dual-Fuel PCI Combustion Controlled by In-Cylinder Stratification of Ignitability
,”
SAE Technical Paper No. 2006-01-0028
.10.4271/2006-01-0028
4.
Hanson
,
R. M.
,
Kokjohn
,
S. L.
,
Splitter
,
D. A.
, and
Reitz
,
R. D.
,
2010
, “
An Experimental Investigation of Fuel Reactivity Controlled PCCI Combustion in a Heavy-Duty Engine
,”
SAE Int. J. Engines
,
3
(
1
), pp.
700
716
.10.4271/2010-01-0864
5.
Kokjohn
,
S. L.
,
Hanson
,
R.
,
Splitter
,
D.
,
Kaddatz
,
J.
, and
Reitz
,
R.
,
2011
, “
Fuel Reactivity Controlled Compression Ignition (RCCI) Combustion in Light- and Heavy-Duty Engines
,”
SAE Int. J. Engines
,
4
(
1
), pp.
360
374
.10.4271/2011-01-0361
6.
Splitter
,
D.
,
Hanson
,
R.
,
Kokjohn
,
S. L.
, and
Reitz
,
R.
,
2011
, “
Reactivity Controlled Compression Ignition (RCCI) Heavy-Duty Engine Operation at Mid-and High-Loads With Conventional and Alternative Fuels
,”
SAE Technical Paper No. 2011-01-0363
.10.4271/2011-01-0363
7.
Kokjohn
,
S. L.
,
Hanson
,
R. M.
,
Splitter
,
D. A.
, and
Reitz
,
R. D.
,
2011
, “
Fuel Reactivity Controlled Compression Ignition (RCCI): A Pathway to Controlled High-Efficiency Clean Combustion
,”
Int. J. Engine Res.
,
12
(
3
), PP.
209
226
.10.1177/1468087411401548
8.
Hanson
,
R.
,
Kokjohn
,
S. L.
,
Splitter
,
D.
, and
Reitz
,
R.
,
2011
, “
Fuel Effects on Reactivity Controlled Compression Ignition (RCCI) Combustion at Low Load
,”
SAE Int. J. Engines
,
4
(
1
), pp.
394
411
.10.4271/2011-01-0361
9.
Curran
,
S. J.
,
Prikhodko
,
V. Y.
,
Cho
,
K.
,
Sluder
,
C.
,
Parks
,
J.
,
Wagner
,
R.
,
Kokjohn
,
S. L.
, and
Reitz
,
R.
,
2010
, “
In-Cylinder Fuel Blending of Gasoline/Diesel for Improved Efficiency and Lowest Possible Emissions on a Multi-Cylinder Light-Duty Diesel Engine
,”
SAE Technical Paper No. 2010-01-2206
.10.4271/2010-01-2206
10.
Northrop
,
W. F.
,
Fang
,
W.
, and
Huang
,
B.
,
2013
, “
Combustion Phasing Effect on Cycle Efficiency of a Diesel Engine Using Advanced Gasoline Fumigation
,”
ASME J. Eng. Gas Turbines Power
,
135
(
3
), p.
032801
.10.1115/1.4007757
11.
Splitter
,
D.
,
Reitz
,
R.
, and
Hanson
,
R. M.
,
2010
, “
High Efficiency, Low Emissions RCCI Combustion by Use of a Fuel Additive
,”
SAE Int. J. Fuels Lubr
,
3
(
2
), pp.
742
756
.10.4271/2010-01-2167
12.
Flowers
,
D. L.
,
Aceves
,
S. M.
, and
Frias
,
J. M.
,
2007
, “
Improving Ethanol Life Cycle Energy Efficiency by Direct Utilization of Wet Ethanol in HCCI Engines
,”
SAE Technical Paper No. 2007-01-1867
.10.4271/2007-01-1867
13.
Rehnlund
,
B.
,
Egebäck
,
K.-E.
,
Rydén
,
C.
, and
Ahlvik
,
P.
,
2007
, “
Heavy-Duty Ethanol Engines
,” Bioscopes Project, Final Report for Lot 2.
14.
Costa
,
R. C.
, and
Sodré
,
J. R.
,
2010
, “
Hydrous Ethanol Vs. Gasoline-Ethanol Blend: Engine Performance and Emissions
,”
Fuel
,
89
(
2
), pp.
287
293
.10.1016/j.fuel.2009.06.017
15.
Dempsey
,
A. B.
, and
Reitz
,
R. D.
,
2012
, “
Reactivity Controlled Compression Ignition Using Premixed Hydrated Ethanol and Direct Injection Diesel
,”
ASME J. Eng. Gas Turbines Power
,
134
(
8
), p.
082806
.10.1115/1.4006703
16.
Dempsey
,
A. B.
,
Walker
,
N. R.
,
Splitter
,
D.
,
Wissink
,
M.
, and
Reitz
,
R. D.
,
2012
, “
Characterization of Reactivity Controlled Compression Ignition (RCCI) Using Premixed Hydrated Ethanol and Direct Injection Diesel in Heavy-Duty and Light-Duty Engines
,”
THIESEL 2012 Conference Thermo- Fluid Dynamics Processing Direct Injection Engines
, Valencia, Spain, Sept. 11–14.
17.
Heywood
,
J. B.
,
1988
,
Internal Combustion Engine Fundamentals
,
McGraw-Hill Inc
, New York.
18.
Hashimoto
,
K.
,
2007
, “
Effect of Ethanol on the HCCI Combustion
,”
SAE Technical Paper No. 2007-01-2038
.10.4271/2007-01-2038
19.
Fang
,
W.
,
Huang
,
B.
,
Kittelson
,
D. B.
, and
Northrop
,
W. F.
,
2014
, “
Dual-Fuel Diesel Engine Combustion With Hydrogen, Gasoline and Ethanol as Fumigants: Effect of Diesel Injection Timing
,”
ASME J. Eng. Gas Turbines Power
,
136
(
8
), p.
081502
.10.1115/1.4026655
You do not currently have access to this content.